MANAGEMENT PLANS — THE NATIONAL FORESTS 



47 



DISCUSSION OK CKIISE 



The Govermneut land ou this area was cruised iu 1910. The trees were 

 tallied by 2-inch diameter classes, the number of logs per tree not being tallied. 

 Volumes were computed from especially prepared volume tables. Trees from 

 12 to 20 inches d. b. h. were not tallied. 



Checking the estimate for 1,300 acres of cut-over land against the cut and 



the amount left for the same area gives the following result: 



Board fe«t 



Cut 34, 541. 000 



L€ft 6. 425, 900 



Totnl 40, 066. 000 



Estimate ;i.-). !tJK. lOO 



Difference 5. 038, 800 



Underestinmte per ceut-_ 12. ?, 



A comparison of the Forest Service cruise on 4.100 acres on tlie soutli side 

 of the area with the cruise made by the University of California Forest School 

 on the same area results as follows: 



Board feet 



University of California Forest School estimate 151.767,000 



Forest Service estimate l.-?0, 720, 000 



IMffcrf-nc."' _ 21. 047,000 



A part of the underestimate of the Forest Service cruise was probal)ly due 

 to the fact that trees from 12 to 20 inches d. b. h. were not included. 



FIRE HAZARD 



This unit would be classed as an area of low fire hazard for the following 

 reasons : 



1. A heavy snowfall, with cool nights during most of the year, prevents a 

 rapid drying out of the area. 



2. The entire area is directly under the eye of the Spanish Peak lookout, so 

 fires should be detected when small. 



3. All parts of the area .ire readily accessible by roads and trails. 



4. There is a good supjily of labor close at hand. 



5. The area is comi)iiratively free from the two chief causes of fire.s — 

 lightning and campers. 



Suiiivuinj of flrr ncord far htxt 11 years 



.\creago 

 burned 



Year 



.N'uml)<>r . .KcTvagc 

 (if fires 1 burnod 



I 1M» , 3 



I 1820 



1921 



Total 



.\verntfc per your 



On the imsls of the fire record for tlie bist 11 years llie loss from lire during 

 the llrsl cutting cycle would not he lieavy. A total of '-'.KH' acres woid<i be 

 burned over, but only part of this would fall on virgin timl>erland, and the loss 

 on this should not be high. The main loss would come thmngb the d(»stnic- 

 tlon of poles and advance repi'otluction. With the steady ImprovennMit in 

 the flre-i»rote(tion system, nortnal loss from fire should not seriously Interfere 

 with the plan for the institution of sustjiined yield. 



GROW Til AMI YIKI » 



C.rowth and yield data for mixed stands are very meager. Tlie prctlileni <»f 

 predicting yield for the second culling cycle and for the rotjitlon jieriod Is 



16.1 per cent of Forest Service ewllinato. 



